Evolution of brightness and magnetic features of young solar-type stars II: The young F8 star HIP 71933
Monthly Notices of the Royal Astronomical Society(2023)
摘要
Abstract The early, active history of our Sun is still not fully understood. Observations of the magnetic fields on active young solar-type stars allows us an insight into the early evolution of our Sun. Here we present Doppler and Zeeman Doppler images of the young late-F star HIP 71933 (HD 129181) at multiple epochs to add to the growing data about the evolution of magnetic cycles in solar-type stars. Spectroscopic data were obtained over seven epochs spanning ten years of observations, with two epochs including spectropolarimetric data. The brightness maps at all epochs show a consistent spot activity in a non-uniform ring at a latitude of approximately +60○ with no polar spot present in any epoch. The two magnetic field maps taken ∼2 years apart show a strong poloidal field configuration with most of the poloidal field energy in the dipolar configuration. The magnetic maps show no evidence of a polarity reversal. We were able to measure the differential rotation from one of the seven epochs using the brightness data finding a dΩ of 0.325 ± 0.01 rad d−1. The values for rotational period and differential rotation found for HIP 71933 are consistent with values found for other late-F or early-G stars. The dominant poloidal features and the limited spots at the pole are unusual for a rapidly rotating star but not unique.
更多查看译文
关键词
line: profiles, stars: individual: HIP 71933, stars: magnetic fields, stars: solar-type, starspots
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要